kWh Cost Calculator
Calculate electricity cost from appliance wattage, hours of use and your per-unit rate — kWh consumed plus cost per day, month and year, free.
About the kWh Cost Calculator
This free kWh cost calculator turns an appliance's wattage and daily hours into electricity units (kWh) and money: kWh = watts × hours ÷ 1000, cost = kWh × your per-unit rate. Enter any rate — rupees, dollars or cents — and see the cost per day, for your billing period and per year.
It's built for the questions behind a heavy electricity bill: a 1,500 W air conditioner running 8 hours a day consumes 360 units a month — Rs. 18,000 at a Pakistani rate of Rs. 50/unit — while a 75 W ceiling fan on for 12 hours costs about Rs. 1,350 and an LED bulb barely Rs. 90. Seeing the per-appliance breakdown shows exactly where the units go.
A built-in table prices common appliances — fridge, AC, fan, LED bulb, TV — at whatever rate you enter, so you can compare before deciding what to switch off.
How to Use the kWh Cost Calculator
- 1Enter the appliance wattage from its label (e.g. 1500 W for a 1-ton AC).
- 2Set hours used per day and the number of days (30 for a monthly bill).
- 3Enter your electricity rate per kWh — the per-unit price on your bill.
- 4Read the kWh consumed and the cost per day, period and year, plus the appliance comparison table.
Frequently Asked Questions
How do I calculate electricity cost from watts?
kWh = watts × hours ÷ 1,000, then multiply by your per-unit rate. Example: a 1,500 W AC for 8 hours uses 12 kWh a day; at Rs. 50 per unit that's Rs. 600 per day or Rs. 18,000 over 30 days.
How much does an AC add to the bill in Pakistan?
A 1.5-ton AC drawing about 1,800 W for 8 hours daily uses 432 units a month. At Rs. 50–65 per unit that's Rs. 21,600–28,080 monthly — and higher usage can push you into a more expensive tariff slab, raising the rate on every unit.
How many units does a refrigerator use per month?
A typical 150 W refrigerator whose compressor runs about 8 hours a day uses around 36 kWh (units) per month — Rs. 1,800 at Rs. 50/unit. Inverter models can cut that by 30–50%; old or poorly sealed fridges use considerably more.
What is 1 unit of electricity?
One unit on your bill is 1 kilowatt-hour (kWh) — 1,000 watts running for one hour. A 100 W TV takes 10 hours to use one unit; a 2,000 W water heater uses a unit in just 30 minutes.
How much does it cost to run a ceiling fan all day?
A 75 W fan for 12 hours uses 0.9 kWh — Rs. 45 a day or about Rs. 1,350 a month at Rs. 50/unit. Even 24-hour use costs only 1.8 units (Rs. 90) daily, a fraction of air conditioning.
Does this include taxes and fixed charges?
No — it computes energy cost only (kWh × rate). Pakistani bills add fuel price adjustment, duties, GST and fixed charges on top, and slab tariffs mean your marginal rate rises with usage. Enter your bill's highest applicable per-unit rate for a realistic estimate.